In recent years, an optical communication network enabling large capacity data communication at high speed is expanding. The optical communication network is assumed to be mounted from intra-devices to inter-device in the future. A light guide that can be arrayed is expected to realize the print wiring substrate as an optical wiring.
The light guide is formed by a core having a large index of refraction and a clad having a small index of refraction arranged in contact with a periphery of the core, and propagates an optical signal entered to the core while repeating total reflection at the boundary of the core and the clad.
In the midst of such circumstances, particularly in recent years, a flexible (similar to electrical wiring) optical wiring mounted on a bendable display and a more compact and thin commercial-off-the-shelf device is desired to be realized with a light guide. That is, the light guide is desirably a film-shaped light guide.
The photoelectric conversion elements (light emitting and receiving elements) need to be aligned and optically coupled to transmit the optical data using the light guide. The light emitting and receiving elements convert an electrical signal to an optical signal and emit the same, and receive the optical signal and convert the same to the electrical signal. In order to hold the optically coupled state, the light guide needs to be fixed, and the distance between the light emitting and receiving unit of the optical signal in the light emitting and receiving element and an incident/exit port of the optical signal in the light guide and the positional relationship of the same need to be maintained constant.
A method of fixing the light guide includes a method of fixing the light guide with a package as shown in Patent Document 1.
FIG. 29 is a perspective view showing a schematic configuration of a package 105 of an optical module 100 described in Patent Document 1. As shown in FIG. 29, the optical module 100 has a configuration including a light guide 101, an optical element 102, and the package 105 made up of a mounting substrate 103 and a supporting body 104. Specifically, the package 105 is formed by integrating the mounting substrate 103 and the supporting body 104 by adhering the contacting surface of the supporting body 104 adhered with the upper surface of the light guide 101 and the contacting surface of the mounting substrate 103 mounted with the optical element 102 with the direction of the optical element 102 with respect to the light guide 101 as the downward direction. In this case, a light guide supporting surface 106 of the mounting substrate 103 adheres with the light guide 101, and thus the light guide 101 is also supported by the mounting substrate 103. In other words, the light guide 101 is supported so as to be sandwiched from both sides by the supporting body 104 and the mounting substrate 103.
According to the configuration of adhering the contacting surface of the supporting body 104 and the contacting surface of the mounting substrate 103 for supporting the light guide 101, the positional relationship of the light guide 101 and the optical element 102, and the distance between the incident/exit port of the optical signal in the light guide 101 and the optical element 102 can be maintained constant.    Patent document 1: Japanese Unexamined Patent Publication No. 2006-39255 (date of publication: Feb. 9, 2006)